The principle of the microwave-heated conveyor belt vulcanizing machine is mainly based on microwave heating technology. Its core lies in using microwave energy to heat rubber and other media as a whole, achieving rapid vulcanization. The following is a detailed analysis of its principle:
First, the basic principle of microwave heating
Microwave refers to electromagnetic waves with wavelengths ranging from 0.1 to 1000mm and corresponding frequencies from 0.3 to 300GHz. When microwaves encounter polar molecular dielectric materials, dipoles will form in the dielectric materials or the existing dipoles will rearrange and reorient. Under the effect of high-frequency electromagnetic fields, these orientation movements constantly change at a frequency of billions of times per second, causing intense molecular movement and collision friction, achieving “stirring” at the molecular level and thereby generating a large amount of heat. This kind of thermal energy is generated by the loss of electric field energy by the medium material itself. Therefore, microwave heating is a process in which electrical energy is directly converted into thermal energy within the medium.
Second, the application of microwave heating in vulcanization of conveyor belts
Overall heating: Microwave heating can penetrate microwave energy into the interior of the heated medium (such as rubber), directly achieving overall heating. This is different from traditional heating methods (such as steam heating, far-infrared heating, etc.). Traditional heating methods conduct heat from the outside to the inside of the medium, which is slow in heating speed and prone to uneven temperature.
Rapid temperature rise: As microwave heating is an overall heating process, rubber materials can be rapidly heated to the vulcanization temperature. This process usually only takes tens of seconds to one or two minutes, significantly reducing the vulcanization time.
Good vulcanization uniformity: Microwave heating heats the rubber material both inside and out simultaneously, ensuring good temperature uniformity and avoiding the uneven vulcanization phenomenon caused by uneven heat conduction in traditional heating methods.
Environmental protection and energy conservation: During the microwave heating process, no open flame or harmful gases are produced, making it a clean heating method. Meanwhile, due to its high heating efficiency, it can significantly reduce energy consumption.
Third, the process flow of the microwave heating conveyor belt vulcanizing machine
The process flow of a microwave heated conveyor belt vulcanizing machine usually includes the following steps:
Rubber extrusion: The rubber raw materials are extruded into the required shape and structure through an extruder.
High-temperature setting: The freshly extruded rubber is rapidly vulcanized and set on its surface at high temperatures to prevent deformation or adhesion to the conveyor belt and damage to its surface.
Microwave vulcanization: Rubber products are conveyed into the microwave vulcanization device through conveyor belts or rollers, and microwave energy is used to heat the rubber as a whole, rapidly raising the temperature to the vulcanization temperature.
Hot air vulcanization: To ensure that rubber products are fully vulcanized, they are usually sent into hot air vulcanization equipment and vulcanized for a period of time under the condition of maintaining a certain temperature.
Cooling and cutting: After vulcanization, the rubber products are cooled to a temperature suitable for operations such as cutting and collection, and then cut and collected.